The invention relates to a sheet metal stud, and in particular to a sheet metal stud adapted to be partially embedded in a thin wall panel of cast material, such as concrete, for reinforcement of such a panel, and to a composite thin wall panel of cast material, such as concrete, having reinforcing studs partially embedded in said panel, and to a method of forming a composite panel.
Steel studs of a wide variety have been proposed for erecting structures. Usually such studs are used to replace wooden studs. Concrete panels are also in wide use for attachment to the exterior of a structure to provide for a wide variety of functional and aesthetic effects. Concrete panels are usually of relatively heavy thick material of great weight. Great costs are involved in both materials, labor transportation, and erection of such heavy panels. Proposals have been made for using panels of reduced thickness. Such thin wall panels are reinforced by a framework of metal studs. Usually edges or flanges of the metal studs are partially embedded in the concrete. The studs extend out from the panels and provide great strength to the panels. The studs are usually located at the usual spacings required in the construction of the inside wall and this facilitates the erection and attachment of the wall panels to the structure. Usually the inside surfaces of the resulting walls are covered in with wall sheeting, typically plaster wallboard. The sheeting is often attached directly to the metal studs. The space between the concrete panels and the inner sheeting is usually insulated with suitable batts or the like. However it is known that the metal studs conduct heat from the building interior to the concrete panels and there are thus substantial heat losses through the panels due to such metal studs.
Accordingly studs have been proposed with reduced heat transfer properties. These studs were formed with generally triangular or trapezoidal openings. The orientation of alternate adjacent openings was reversed. In this way the openings were positioned so as to define between them diagonal struts extending across the studs. Heat could pass along the struts but not where there were openings. Heat losses across the stud were thus reduced since there was less metal through which the heat could pass. However when these panels are erected, it is usual for the builder to run services through the studs, within the wall. Where the openings are of these specialized shapes the services must be such that they can fit the openings, and all openings is all the studs in a wall would preferably be aligned with one another to facilitate the passage of services therethrough. It is not possible to the builder to cut away any of the diagonal struts to provide larger openings for services, since this would drastically reduce the strength of the studs.
Another problem arose in that the triangular openings were formed with edge flanges around their perimeter. It is desirable that the edge flanges shall be formed substantially into a right angle bend relative to the plane of the sheet metal. This right angle bend increases the strength of the overall stud. However where these edge flanges extended around an angular corner of the generally triangular or trapezoidal shaped opening there was a tendency for the sheet metal in the edge flange to crack. Consequently the corners had to be radiussed or rounded out. This meant that there was more metal at each of the corners, than was desirable for heat transfer, and thermal losses could occur. Also at these angular corners it was found that it was not possible to bend or form the edge flanges of the struts in the studs into a full right angle bend. Instead the angle of the flanges at the corners was something less than a right angle. This was found to reduce the problems of cracking of the sheet metal at these corners. However this solution was not totally satisfactory since, by reducing the angle of the edge flange, the strength of the overall stud was also reduced. Another problem arose in cutting these studs to length. As explained above the openings were arranged in pairs, in which the orientations of the two openings was alternately reversed, with one triangle facing one way and the next facing the opposite way. Construction practices for such studs require that all of the openings of a particular orientation, in all of the adjacent studs in a wall frame, shall line up. This is required to facilitate passing of services through the studs. However due to the alternating orientation of the openings there were problems in cutting off the studs to a specific length. This was done as part of the manufacturing process, on the production line. If cutting was carried to a specified length which was not an exact multiple of the spacing of the openings, then the cutting step resulted in cutting off waste end portions of studs equal in length to the space occupied by two openings, in many cases. This was waste metal and increased the cost of the building.
It has now been surprisingly found that the use of the specialized trapezoidal shapes of these stud openings, defining diagonal struts, is not always necessary. In fact a reduction of heat transfer across the stud is possible using circular openings in the studs. In other cases the openings can be made which are not completely circular, but have rounded corners and some more or less straight sides. In this case the corners could be rounded out over a much greater radius than was formerly used. One of the corners may even be semi-circular. This was not thought to be possible since circular openings, or openings with long radius corners, or semi-circular corners would leave excessive metal in the stud which would still cause heat transfer losses. While this would appear to be correct, in theory, it has been found that by the use of relatively small additional openings, the actual heat transfer path can be so reduced, at critical points in the stud, so as to substantially improve on the heat transfer reduction achieved by the use of the specialized triangular or trapezoidal openings and diagonal struts of earlier studs, and could be generally equivalent to the heat transfer curves of wooden studs.
Circular openings, or openings with rounded corners, avoid the problems caused by the corners of the triangular or trapezoidal openings and splitting of metal, and results in a much stronger stud. The use of circular or rounded openings greatly facilitates high speed manufacture of such studs by punching out circular blanks, or blanks with semicircular corners, from the sheet metal. This leads to economies from higher production speeds.
The blanks of sheet metal removed in this process provide secondary products of a more convenient shape. This leads to economies in the process since the blanks can be remanufactured into secondary products and can thus be sold instead of being discarded as waste. In the case of completely circular openings the cutting to length of such studs becomes easier since every opening is the same shape and the same spacing along the stud. This leads to economies in manufacture since the studs can now be cut to length with less wastage of material than was possible in the past.
Most importantly, the circular or semi-circular openings remove many of the problems for the builder who wishes to pass services through the studs within the wall. Much larger diameter pipes can now be fed through the studs, than was possible with studs using trapezoidal openings. This leads to less sales resistance due to a greater acceptance of the product in the market place. Finally, cutting to length of a stud with identical circular openings may result in much less wastage of material and this is another cost saving.
It will be appreciated that a stud which improves on all these problems associated with prior studs, will have application in general use, apart from the reinforcement of a concrete panel. Such a general purpose stud will have minor modifications from the panel reinforcement stud, but will be otherwise similar.
The invention seeks to overcome the various disadvantages of earlier systems by providing a composite construction panel and comprising, a thin panel of concrete material, a reinforcing grid of sheet metal studs comprising parallel studs and top and bottom members, wherein said studs have embedment portions which are actually embedded into the concrete panel, and wherein each of said studs comprises, a web defining a free edge, right angular flange formed on said free edge, an angular edge strip formed along the free edge of said right angular flange, an embedment flange portion formed along the opposite edge of said web, a retention edge strip formed on said embedment flange portion at an angle thereto, and, a plurality of spaced apart embedment flange openings formed in said angled flange.
The invention further provides such a composite construction panel wherein said embedment flange openings are formed by a series of semi-arcuate openings located spaced apart lengthwise along said embedment flange.
The invention further provides such a composite construction panel and including web main openings of generally circular shape formed through said web between said embedment flanges and said free edge flanges, and edges of said circular openings being formed out of the plane of said web to define an annular ring. The invention further provides a reinforcing stud for use in forming a composite construction panel wherein the panel is formed in a thin panel of cast material such as concrete type material, and a reinforcing grid of sheet metal studs wherein said studs have embedment portions which are embedded into the panel, and wherein each of said studs comprises, a web defining a free edge, right angular flange formed on said free edge, an angular edge strip formed along the free edge of said right angular flange, an embedment flange portion formed along the opposite edge of said web, a retention edge strip formed on said flange portion at an angle thereto and, a plurality of embedment openings formed longitudinally spaced apart along said embedment flange portion.
The invention further provides such a reinforcing stud wherein said embedment openings are formed by a series of semi-arcuate openings located spaced apart lengthwise along said embedment flange portion.
The invention further provides such a reinforcing stud, in one embodiment, including main web openings of generally circular shape formed through said web between said embedment flange portions and said free edge flanges, and edges of said circular openings be formed out of the plane of said web to define generally annular rings.
The invention further provides such a reinforcing stud, in another embodiment, including web openings of generally non-circular shape formed through said web between said embedment flange portions and said free edge flanges, in which the non-circular openings define corners have long radius curvature, and one of said corners being substantially semi-circular, and edges of said non-circular openings be formed out of the plane of said web to define generally right-angular edges flanges.
The invention provides a further form of such a stud which is formed with generally circular indentations or depressions in the sheet metal in spaces spaced from said main openings, and semi-circular openings formed in said depressions.
The invention provides a further form of such a stud which is formed with a tubular formation along the free edge.
The invention provides a further form of such a stud which is formed without a continuous embedment flange portion. In this embodiment the web is formed as a series of generally V-shaped web portions with spaces therebetween, and with embedment formations at the apex of each V-shaped web portion.
The invention provides a further form of such a stud which is formed with small circular indentations or depressions with openings in the indentations, and in which each opening in each such small indentation is formed as an elongated slot, leaving arcuate portions of sheet metal within the small indentations or depressions, on either side of the slotted opening.
The invention provides a further form of such a stud which is formed with non-circular main openings, having at least one first radius corner formed as an arc of a circle having a first radius, and with two further lesser radius corners formed as arcs of circles having radii less than said first radius.
The invention provides a further form of such a stud which is formed with non-circular main openings as aforesaid and in which circular indentations or depressions are formed in the sheet metal alternately spaced further apart and closer together adjacent said first radius corner and said lesser radius corners respectively, the small depressions having slotted openings formed therein defining arcuate sheet metal portions on either side of such slotted opening.
The invention provides any of such studs, being formed with an embedment flange along one edge having embedment openings in such embedment flange for embedment in a panel of cast material, whereby any of such studs may be used to form reinforcing for a reinforced cast panel.
The invention provides any of such studs, in which the slots in the small depressions are formed with slot edge flanges, the slot edge flanges being formed in a direction opposite to the axis of the depression.
The invention provides any of such studs, in which the right angular flange is formed with a folded strip, to form a double thickness of sheet metal, in the folded strip.
The invention further seeks to provide a method or making a composite construction panel comprising the steps of, assembling a plurality of reinforcing studs, each having webs with circular or non-circular main openings therethrough, in parallel spaced apart relation with said main openings aligned with one another, and with cross members arranged transversely at the ends of said parallel studs thereby forming a grid of studs, said parallel studs having embedment flange portions thereon, pouring cast material such as concrete into a form shaped to provide a planar panel, placing reinforcing mesh in said cast material, placing said grid of studs over said cast material in said form and lowering the same until said embedment flange portions are immersed in said cast material, allowing said cast material to cure, and removing said formed composite panel consisting of cured cast material with said grid of studs secured in and extending from said panel.
The invention further provides a plurality of general purpose studs for use as a replacement for conventional studs in walls, floors, roofs and the like. Such a general purpose studs will be similar to the several embodiments of reinforcement stud described above, but without the embedment flange portion.
The various features of novelty which characterize the invention are pointed out with more particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its use, reference should be made to the accompanying drawings and descriptive matter in which there are illustrated and described preferred embodiments of the invention.